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Date: Fri, 03 Jul 2009 10:37:06 -0400
From: Mathieu Desnoyers <mathieu.desnoyers@polymtl.ca>
To: linux-kernel@vger.kernel.org,
       Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>,
       Dave Jones <davej@redhat.com>, Thomas Renninger <trenn@suse.de>,
       cpufreq@vger.kernel.org, kernel-testers@vger.kernel.org,
       Ingo Molnar <mingo@elte.hu>, rjw@sisk.pl,
       Dave Young <hidave.darkstar@gmail.com>,
       Pekka Enberg <penberg@cs.helsinki.fi>
Subject: [patch 2.6.30 0/4] Fix cpufreq locking dependency
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Hi,

Here is a patchset applying on 2.6.30 which should fix the cpufreq locking
dependency. Sadly, my two main test machines does not seem to support cpufreq,
so I have only been able to perform very light testing. (I can't afford to lock
down my laptop right now).

I went for the most straightforward fix I could think of and kept the current
locking structure. As you will see, the second patch cleans up the error
handling paths of cpufreq add dev, which were a total mess.

As a general recommendation, creating scripts which does, concurrently :

cpu hotplug up/down
cpufreq sysfs actions
change between cpufreq governors
add governors on random CPU numbers

will likely help stress-testing cpufreq locking. I really did not like what I've
seen there. It looked _very_ fragile.

Hopefully this will be better with this patches, but again, testing is welcome.

Thanks,

Mathieu


-- 
Mathieu Desnoyers
OpenPGP key fingerprint: 8CD5 52C3 8E3C 4140 715F  BA06 3F25 A8FE 3BAE 9A68